Solid-state 31P NMR technique will be used to study the structures and development of calcified tissue, using benchmark data on well characterized inorganic phosphates gathered in the past year. 31P and 13C NMR will be used to extend present studies of the conformation of native and synthetic nucleic acids in oriented fiber samples. Development of new NMR techniques will be continued, with emphasis on methods for the detection of very slow molecular motion in solids.